The medical community has been aware of the problem of needlestick injuries for years but only with the advent of HIV AIDS and the discovery of Hepatitis C virus in the 1980s did this problem become a burning issue. The infectivity of blood borne pathogens via needlestick injuries then came into focus. Even so, little progress has been made in the past 20 years.
In some countries, as many as 90% of the injections given are unsafe. Furthermore, 21 million people in developing countries around the world are infected yearly from contaminated syringes (WHO: Immunisation safety priority project, 1999-2005). As a result of needlestick injuries, more than 580 million people in the world are chronic carriers of diseases, and an estimated 1.3 to 1.6 million people die annually.
In the U.S. alone, 1 million healthcare workers have been stuck with hypodermic needles that may be infected with Hepatitis B, Hepatitis C or HIV. Over a thousand of these healthcare workers contracted a serious infection, 80% of which could have been prevented by using appropriate safety devices. As a result, a total of $3 billion per year is spent in the U.S. on needlestick injuries.
In the U.K., an ongoing Royal College of Nursing surveillance project suggests that as many as 100,000 needlestick accidents occur every year. There are currently 12 cases of HIV infection among NHS workers in the U.K. that are suspected to have been caused by needlestick injuries. As a result, needlestick injuries are estimated to cost each NHS trust around £500,000 per year.
The solution to the problem of needlestick injuries is the introduction of medical devices with an engineered safety solution along with adequate training of personnel and the application of universal precautions.
WO 2006/072135 describes a safety device for a needle and syringe comprising a shield that is slideably attached to the body of a syringe and that can be moved between a retracted and shielding position to shield a needle tip. However, the device disclosed in this application must be operated with two hands. Furthermore, in order to retract the shield to expose the needle for use, the user is required to place their hands close to the needle tip. In addition, when the shield is fully retracted and the needle exposed—i.e. the position required for use of the device, the shield fully or partially covers the syringe. As a result, it is difficult for the user to read the scales present on the syringe due to the presence of the shield. A final limitation of this device is that due to its size, the device will take up more room in expensive sharps containers.
Other needle safety devices include that disclosed in US2002/0165498, which describes a safety needle assembly comprising a needle, a spring-driven shield assembly and a safety cap, wherein the shield assembly comprises a plurality of arms that allow sliding of the shield from a retracted to an extended position. However, in order to extend the shield over the needle the user is required to alter their grip, from the position required to operate the needle, to the position required to push against one of the arms of the shield assembly. As a consequence, actuation requires the user to place a thumb or finger in close proximity to the needle tip.
In addition to the above, the above-described devices require the user to retract the device from the injection site thereby exposing the needle before actuation.
EP1350529 describes a safety shield assembly for an intravenous apparatus, wherein the shield comprises a forward shield, a guide element and a locking member. The forward shield comprises a distal blunting end that has a distal aperture and a proximal needle passageway. In the closed position, the needle tip is covered by the distal blunting end. However, the device described in this application is limited to use with blood collection or intravenous infusion devices.
Therefore there exists a need for a needle safety device that can be operated single-handedly and where the user can operate the device without a change in grip and while maintaining hands and fingers safely behind the needle tip. Furthermore, given the high demand for such devices in health services, it is important that such a device can be cheaply and easily produced and has cheap disposal costs. There also exists a need for a needle safety device that can be universally used with a range of medical devices from staked needle syringes to blood collection needles, hypodermic needles and other hollow bore needle devices.